The present invention relates to an improved pull rod structure of a self-opening umbrella and, more particularly, to stretchers having joints, which are made of plastic material and have soft pull rods integrally formed therewith.
FIG. 1 shows an unfolded state of a prior art self-opening umbrella. As shown in this figure, a shaft 11a of a general self-opening umbrella 10a usually has an upper nest 12a, a middle nest 13a, and a lower nest 14a installed thereon. A spring 15a is sleeved on the portion of the shaft 11a between the middle nest 13a and the lower nest 14a. The middle nest 13a joins stretchers 16a. Each of the stretchers 16a has a pull rod 162a thereon. Two ends of each of the pull rods 162a are joined on one of the stretchers 16a and the lower nest 14a, respectively. The stretchers 16a and the pull rods 162a are joined together with hinges. For this kind of joining, each of the stretchers 16a needs to have a joint 161a sleeved into one of the pull rods 162a. A wire penetrates through shuttle holes 1621a of the pull rods 162a and is then locked onto the lower nest 14a to join the pull rods 162a and the lower nest 14a together. Because the joints 161a and the pull rods 162a are made of metallic material, it is very cumbersome to form holes and grooves on the joints 161a and the pull rods 162a, to achieve joining with hinges, and to install the joints 161a on the stretchers 16a. The assembly is also inconvenient. Moreover, if subassemblies need to be replaced, the disassembly is also very troublesome.
Accordingly, the assembly of the above self-opening umbrella is difficult, the manufacture of subassemblies is very cumbersome, and the disassembly is hard if subassemblies need to be replaced. In other words, the above self-opening umbrella has inconvenience and drawbacks in practical use. The present invention aims to resolve the above problems in the prior art.
The primary object of the present invention is to provide an improved pull rod structure of a self-opening umbrella to facilitate the assembly of the self-opening umbrella, and to simplify the manufacture of subassemblies thereof so that replacement of the subassemblies is very convenient.
To achieve the above object, the present invention provides an improved pull rod structure of a self-opening umbrella comprising joints made of plastic material and disposed on stretchers. Each of the joints has a soft pull rod integrally formed therewith. The other end of each of the soft pull rods has an installation end installed in a lower nest. Because the soft pull rods can be bent many times, they can substitute for a complicated pull rod structure in the prior art to simplify the assembly of a self-opening umbrella.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: